Question 850
{"accessible":false,"alternatives":[{"id":4298,"text":"a non-functioning adenoma usually results in substantial elevation of prolactin due to stalk effect. "},{"id":4299,"text":"an elevated prolactin level of less than ten times normal is unlikely to be due to a microadenoma. "},{"id":4300,"text":"in this patient, a dopamine antagonist is a likely cause of mildly elevated prolactin levels."},{"id":4301,"text":"in this setting, any area of relatively delayed enhancement within the pituitary on dynamic enhanced sequences likely represents a microadenoma."}],"archived":false,"correctAlternativeId":4300,"explanation":"\u003cp\u003eMany antipsychotic medications (such as haloperidol and chlorpromazine) are dopamine antagonists\u0026nbsp;and will, therefore, impair the normal tonic inhibition of prolactin secretion.\u0026nbsp;\u003c/p\u003e\u003cp\u003eKnowing the prolactin level is really important. Less than 96ng/ml (~2 times normal) is very unlikely to be due to an adenoma, whereas over 200ng/ml (roughly\u0026nbsp;5 times normal) is usually due to an adenoma.\u0026nbsp;\u003c/p\u003e\u003cp\u003eMost non-functioning macroadenomas, prolactin levels are near-normal rather than elevated. This is believed to be due to chronic mass-effect leading to generalized pituitary insufficiency\u003c/p\u003e","id":850,"imageUrl":null,"imageAttribution":null,"imageAttributionCaseInfo":null,"firstQuestionPath":"/questions/2302","nextQuestionPath":"/articles/pituitary-gland/questions/849","relatedArticles":[{"id":51532,"title":"Elevated prolactin (differential)","link":"/articles/elevated-prolactin-differential?lang=us"}],"alsoUsedIn":[{"id":80,"kind":"Course","title":"[TRIAL] Pituitary Region Learning Pathway - page 80","link":"https://radiopaedia.org/courses/trial-pituitary-learning-pathway/pages/80"},{"id":80,"kind":"Course","title":"Pituitary Region Learning Pathway - page 80","link":"https://radiopaedia.org/courses/pituitary-learning-pathway/pages/80"}],"stem":"\u003cp\u003eA young woman with a history of schizophrenia presents for an MRI examination of the pituitary gland to assess for the presence of a microadenoma as the cause for increased prolactin. She has had a normal CT of the brain. Which of the following is most accurate?\u003c/p\u003e","menuLinks":[{"text":"Report problem with question","url":"https://docs.google.com/forms/d/e/1FAIpQLSfO3soWYhOjJ7yErSysyCe5V4A1CqW7WK3rDA7MtAkecMGqNw/viewform?entry.1624461248\u0026entry.553583435=https://radiopaedia.org/questions/850"}],"attemptsPercentages":[{"alternativeId":"4299","percentage":4},{"alternativeId":"4298","percentage":2},{"alternativeId":"4300","percentage":88},{"alternativeId":"4301","percentage":6}],"promptToLogin":false,"questionManager":false,"articleId":"pituitary-gland"}